1. Field of the Invention
This invention relates to optical systems, and more specifically, to optical systems that incorporate an optical resonator in either the illumination path or a measurement path in order to enhance the optical performance of the system.
2. Description of the Related Art
Optical measurement systems, optical storage and retrieval systems and other optical systems may be limited by many factors, including illumination beam size, diffraction limit, detector noise, and resolution. The above-incorporated patent applications disclose techniques for enhancing the performance of a variety of optical systems and improving the resolution and sensitivity of optical technologies disclosed therein.
It would be further desirable to improve the performance of the systems disclosed in the above-referenced patent applications, as well as other optical systems, in order to further improve their performance.
The foregoing objectives are achieved in an optical system and method and apparatus having improved optical performance. The system includes an optical illumination subsystem, an optical detection subsystem and an optical resonator disposed in at least one optical path between the illumination system and the detection system. The system further includes a tuning stage that may be incorporated within the resonator or the illumination subsystem to provide adjustment of the resonance of the optical resonator either by adjusting the wavelength of light passing through the resonator or by adjusting an optical path length within the resonator in order to assure the proper resonance operating point.
Control signals used in a closed-loop system for controlling the resonator may also be used for output of measured data. In particular, components of the resonance control signal provide information about the changing resonant path length of the resonator, which may be a measurement function of the system.